GB956453A - Preparation of particulate polymers - Google Patents

Abstract

Particulate polymers are made by polymerizing at 40 DEG to 200 DEG C at least one monomer having a CH2=C< group in an agitated organic liquid which is inert to the monomer charge, is water-immiscible, hydrocarbon-miscible, a nonsolvent for the resultant polymer and which contains a polymerization initiator and, as a granulating agent, a water-insoluble copolymer of 99 to 70% of at least one C1-C18 alkyl acrylate or methacrylate, in which the size of the alkyl group(s) is sufficiently large to solubilize the copolymer in the organic liquid medium, and 1 to 30% of at least one nitrogen compound having the formulae: <FORM:0956453/C3/1> where each of the R11 symbols represents hydrogen or a lower alkyl group, <FORM:0956453/C3/2> wherein R0 is hydrogen or a C1-C12 alkyl group and n is an integer of 1 to 4, or CH2=C(R)AYNR1R2 wherein R is hydrogen or methyl, A is oxygen, sulphur, <FORM:0956453/C3/3> or <FORM:0956453/C3/4> , Y is a C2-C8 alkylene group, R1 and R2, when not directly attached together, are phenyl, benzyl, methylbenzyl, cyclohexyl or C1-C6 alkyl groups, and, when directly connected together, represent a morpholino, piperidino or pyrrolidino residue. Polymerizable CH2=C< monomers specified are C1-C4 alkyl methacrylates, C1-C18 alkyl and cyclohexyl acrylates, styrene, vinyl toluene, alpha-methyl styrene, vinyl acetate and mixtures thereof with vinyl chloride, acrylic and methacrylic acids and their amides, acrylonitrile, itaconic acid, dimethylaminoethyl acrylate, N-vinyl -2- pyrrolidone, ureidoethyl vinyl ether, divinyl benzene and ethylene glycol dimethacrylate, which may be copolymerized with each other or with maleic anhydride. Organic liquid polymerization media specified include aliphatic and aromatic chlorinated hydrocarbons, aliphatic, cycloaliphatic and aromatic hydrocarbons petroleum fractions, terpenes, butyl stearate, ethyl dodecyl ether, ethylene glycol dodecyl ether and methyltert.-dodecyl sulphide. Polymerization initiators specified are benzoyl peroxide, tert.-butyl hydroperoxide, tert.-butyl peracetate, azodiisobutyronitrile and dimethyl azodiisobutyrate. Granulating agents specified are copolymers of (a) vinyl pyridine and butyl, lauryl and stearyl methacrylates, (b) dimethylaminoethyl methacrylate and butyl lauryl and stearyl methacrylates, (c) N-vinyl -2- pyrrolidone and butyl, lauryl and stearyl methacrylates, and (d) N-vinyl -2- pyrrolidone, butyl acrylate and a mixture of C12-C18 alkyl methacrylates. The examples describe the application of the process to produce polymers of (1) methyl methacrylate; (2) ureidoethyl vinyl ether; (3) methyl methacrylate+ethyl methacrylate; (4) acrylonitrile+butyl acrylate; (5) vinyl acetate; (6) acrylonitrile+2-ethylhexyl acrylate; (7) methyl methacrylate+ethyl acrylate; (8) ethyl acrylate+methacrylic acid; (9) styrene+divinyl benzene; (10) vinyl toluene+divinyl benzene; (11) styrene+maleic anhydride; (12) alpha-methylstyrene; (13) N-vinyl -2- pyrrolidone and (14) acrylamide. Specification 956,454 is referred to.